Round feeding mechanism for automatic guns for discharging rounds from a round magazine



July 18, 1967 E. w. JAFVERT 3,331,231

ROUND FEEDING MECHANISM FOR AUTOMATIC GUNS FOR DISCHARGING ROUNDS FROM AROUND MAGAZINE 3 Sheets-Sheet 1 Filed March 7', 1966 A T'TORNE rs3,331,281 HARGING July 18, 1967 E. w. JAFVERT SM FOR AUTOMATIC GUNS FORDISC ROUND FEEDING MECHANI ROUNDS FROM A ROUND MAGAZINE Filed March '7,1966 3 Sheets-Sheet 2 INVENTOR. W/L HELM aim/127" BY Arrammar July 18,1967 E W.Ji- '\FVERT 3,331,281

ROUND FEEDING MECHANISM FOR AUTOMATIC GUNS FOR DISCHARGING ROUNDS FROM AROUND MAGAZINE Filed March 7, 1966 3 Sheets-Sheet J INVENTOR. Ek/KVV/LHELM JA ME/er BY Emma Avrawer:

United States Patent O 3,331,281 ROUND FEEDING MECHANISM FOR AUTOMAT- ICGUNS FOR DISCHARGING ROUNDS FROM A ROUND MAGAZINE Erik Wilhelm Jiifvert,Karlskoga, Sweden, assignor to Aktiebolaget Bofors, Bofors, Sweden, aSwedish company Filed Mar. 7, 1966, Ser. No. 534,967 Claims priority,application Sweden, Mar. 10, 1965, 3,142/ 65 8'Claims. (CI. 8933) Thepresent invention is related to a round feeding mechanism for automaticguns for discharging rounds from a round magazine, which includesseveral vertical round compartments disposed side by side and havinglower open exit ends for the rounds and each capable of holding onestack of rounds disposed one upon the other.

It is desired that automatic guns can be provided with a round magazineof the type mentioned above, as this will make it possible to load morerounds in the gun than if the gun, as in most cases, is provided with around magazine consisting of a single vertical round compartmentdisposed in the same vertical plane as the barrel of the gun straightabove a ramming position for the rounds in the rear prolongation of thebarrel. It is also possible to provide a gun with two round magazines ofthe type first mentioned disposed on opposite sides of the gun, wherebyit will be possible to load the gun with two different types ofammunition so that the type of ammunition can be changed or chosenrapidly during fire. A round magazine of this type must obviously,however, be disposed at the one side of the vertical plane containingthe barrel of the gun and a round feeding mechanism is consequentlynecessary, which can discharge. the rounds one at a time from the roundmagazine, so that the round compartments are emptied in a predeterminedorder, and move the rounds in a direction perpendicular to theirlongitudinal axes to a position in the vertical plane containing thebarrel of the gunv The last mentioned position can then be either aramming position in the rear prolongation of the barrel or anintermediate position, which lies in the same vertical plane as thebarrel but straight above the ramming position. From this intermediateposition the rounds can subsequently be fed downwards into the rammingposition by a special round feeding mechanism.

For discharging the rounds from a round magazine of the type describedit is previously known to use a round feeding carriage, which is locatedunderneath the round magazine spaced from the lower open exit ends ofthe round compartments by a distance at least corresponding to thediameter of the rounds and which is reciprocatingly movable in adirection perpendicular to the longitudinal direction of the rounds andthus perpendicular to the vertical plane containing the barrel of thegun over a distance corresponding to the spacing between the centerlines of adjacent round compartments in the magazine. This round feedingcarriage is provided with a number of round feeder pawls correspondingto the number of round compartments in the magazine. These round feederpawls are arranged one after the other in the direction of movement ofthe feeder carriage with a mutual spacing corresponding to the centerline spacing between adjacent round compartments so that the roundfeeder pawls can engage each one round located in the space between thecarriage and the exit ends of the round compartments. When the roundfeeder carriage is moved towards its discharge position, the roundfeeder pawls will bring along all the rounds located in the spacebetween the feeder carriage and the exit ends of the round compartments,whereby at the end of this discharge movement the round closest toforward discharge end of the feeder carriage will be delivered to aramming position or an intermediate position in the vertical planecontaining the barrel of the gun, at the same time as a new round is feddownwards into the space between the carriage and the exit ends of theround compartments from the round compartment still holding any rounds,which is furthest away from the discharge end of the round feedercarriage. Thereafter the round feeder carriage is to be returned to itsinitial or neutral position in such a way that the rounds located in thespace between the round feeder carriage and the exit ends of the roundcompartments are not simultaneously displaced.

A round feeding mechanism of this type presents several problems, forwhich satisfactory solutions must be found. Thus for instance therounds, which are brought along by the round feeder carriage during itsdischarge movements and to which consequently a considerable kineticenergy is imparted, must be retarded in some suitable way at the end ofthe discharge movement. Furthermore, the rounds located in the spacebetween the round feeder carriage and the exit ends of the roundcompartments must be kept stationary in their positions in some suitableway during the return movement of the feeder carriage. It must also beascertained that the new rounds from the round compartments are feddownwards into the space between the exit ends of the round compartmentsand the round feeder carriage in a correct predetermined order.

The object of the present invention is to provide a round feedingmechanism of the type described above, which is simple, reliable andcompact. The round feeding mechanism according to the invention ischaracterized by two rows of check pawls disposed parallel to thedirection of movement of the round feeder carriage on opposite sidesthereof, each one of said rows comprising a first check pawl for eachround compartment in the round magazine except for the round compartmentfurthest away from the discharge position of the roundfeeder carriage,said first check pawls being pivoted in a vertical plane parallel to thedirection of movement of the carriage about stationary axes locatedstraight below the associated ones of round compartments so as to beswingable between as raised position, in which said first check pawlsare extending obliquely upwards opposite to the direction of thedischarge movement of the round feeder carriage between the roundsdisposed in the space between the carriage and the exit ends of theround compartments, and a depressed position, in which said first checkpawls lie beneath said rounds and consequently can be passed by saidrounds. Furthermore, the mechanism comprises control means for saidfirst check pawls, said control means being responsive to the movementof the round feeder carriage and being coupled to said first check pawlso as to move said check first pawls into their depressed positionbefore the beginning of the discharge movement of the round feedercarriage and to keep the check pawls in this depressed position duringthe first part of the discharge movement of the feeder carriage, untileach check pawl has been passed by one round brought along in thedischarge movement of the round feeder carriage, and subsequently toreturn the check pawls to their raised position before the end of thedischarge movement of the carriage. These first check pawls willconsequently be in their raised position at the end of the dischargemovement of the round feeder carriage and will thereby, as they are inthis raised position extending obliquely upwards opposite to thedischarge position, stop the rounds which are lying in the space betweenthe carriage and the exit ends of the round compartments and which havebeen brought along in the discharge movement of the round feedercarriage. During the first portion of the discharge movement on thecontrary these first check pawls are in their depressed position andwill consequently not prevent the displacement of the rounds lyingbetween the carriage and the exit ends of the round compartments in thedischarge direction. Preferably, the check pawls are moved to theirdepressed position already during the last part of the return movementof the round feeder carriage.

Preferably each one of the two rows of check pawls comprises anadditional, second check pawl for each round compartment closest to thedischarge end of the round feeder carriage, said second check pawl beingalso pivoted in a vertical plane parallel to the direction of movementof the round feeder carriage about stationary axes located straightbelow the associated one of round compartments so as to be swingablebetween a raised position, in which these second check pawls areextending obliquely upwards in the discharge direction between therounds lying in the space between the carriage and the exit ends of theround compartments, and a depressed position, in which these secondcheck pawls lie beneath said rounds and consequently can be passed bythem. These second check pawls are urged by spring means towards theirraised positions and will consequently during the discharge movement ofthe round feeder carriage be automatically pushed down into theirdepressed position against the action of the spring means by the roundsbrought along by the round feeder carriage, whereby these rounds canpass said second check pawls. At the end of the discharge movements,when each one of said sec. ond check pawls has been passed by one round,these second check pawls will, however, be automatically returned by thespring means to their raised position, whereby they will prevent therounds lying in the space between the round feeder carriage and the exitends of the round compartments from being displaced during the returnmovement of the carriage.

In the following the invention will be further described with referenceto the accompanying drawings, in which one embodiment of a round feedingmechanism according to the invention is shown by way of example.

FIGS. 1 and 2 show schematically, seen from the rear end of the gun andin the direction parallel to the barrel; a round magazine, the mostimportant parts of a round feeding mechanism according to the inventionand those parts of the gun, which are of interest in connection withthis round feeding mechanism; FIG. 1 showing the round feeding mechanismduring the discharge movement of the round feeder carriage and FIG. 2showing the round feeding mechanism during the return movement of thecarriage.

FIG. 3 shows the round feeding mechanism more in detail and inperspective seen from its discharge end and with certain parts of themechanism cut away.

FIG. 4 shows a detail of the control means for the check pawls in theround feeding mechanism.

FIG. 5 shows in detail a part of the mechanism for driving the roundfeeder carriage from the recoiling mass of the gun.

FIG. 6 shows in detail a mechanism for driving the round feeder carriagemanually.

FIGS. 1 and 2 show a round magazine 1 comprising six vertical roundcompartments 2, which are arranged side by side and each hold one stackof rounds 3 lying one upon the other. The round compartments are open attheir lower exit ends and are provided with spring means (not shown inthe drawing) exerting a permanent downwards pressure upon the roundslying in the round compartmets. Underneath the round magazine there is around feeding mechanism comprising a stationary base plate 4 and a roundfeeder carriage 5 reciprocatingly movable in the base plate in adirection perpendicular to the longitudinal direction of the rounds.During the discharge movement of the round feeder carriage 5, that iswhen the carriage is moving to the right in FIGS. 1 and 2, a round will,as will be further described in the following, be delivered to anintermediate or ready position in a locking device consisting of twoflaps 6, which are swingable about mutually parallel axes and arespring-loaded in direction towards each other. This ready position liesin the same vertical plane as the barrel of the gun (not shown in thedrawing) and straight above a loading tray 7, which is arranged tosupport and guide the rounds during the ramming operation. The upperside of this loading tray will consequently serve as a ramming path forthe rounds. 8 designates a vertically reciprocatingly movabledown-feeder, which is controlled from the recoiling mass of the gun insuch a way that it will during the recoil movement of the gun push around lying in the ready position on the flaps 6 between the flapsdownwards onto the loading tray 7, that is to the ramming position.During the recuperation movement of the recoiling mass of the gun thedown-feeder 8 is returned to its upper position so that at the end ofthe recuperation movement a new round can be delivered from the roundmagazine to the ready position on the flaps 6. The down-feeder S can forinstance be controlled by a downfeeding mechanism of the type describedin the copending United States patent application No. 475,939. For theoperation of the present invention, however, it is immaterial in whichway the down-feeding mechanism is designed, wherefore the down-feeder 8can also be controlled in any other suitable manner. Nor is it necessaryfor the round feeding mechanism according to the invention that therounds are fed to a ready position, but the round feeding mechanismaccording to the invention can also be used for feeding the roundsdirectly to the ramming position, if the other parts of the gun aredesigned to permit this. When the gun is firing automatically, a newround must conseqeuntly be discharged from the round magazine anddelivered to the ready position on the flaps 6 during the recuperationof the recoiling mass of the gun, that is the round feeder carriage 5must be moved to the right in FIGS. 1 and 2 during the recuperationmovements of the recoiling mass and be returned to the left in FIGS. 1and 2 during the recoil movement of the recoiling mass.

As can be most readily seen in FIG. 3, the round feeder carriage 5supported by the base plate 4 is provided with two parallel rows ofround feeder pawls 9 extending in the direction of movement of thecarriage. The round feeder pawls 9 are mounted in pairs on opposite endsof shafts 10 mounted for rotation in the feeder carriage. The mutualspacing between the shafts 10 corresponds to the spacing between thecenter lines of two adjacent round compartments 2 in the round magazine.The feeder pawls 9 are swingable between the raised position shown inFIG. 3, in which the pawls are extending obliquely upwards from theupper side of the feeder carriage in the discharge direction of thecarriage and have their upper ends lying behind each one of the roundslying in the space between the feeder carriage and the exit ends of theround compartments, and a depressed position, in which the feeder pawlsare substantially horizontal and lie below the upper side of the feedercarriage. Each one of the shafts 10 is provided with a coil spring 11urging the feeder pawls 9 attached to the shaft towards their raisedposition. The feeder carriage 5 is running in the base plate 4 on wheels12 journalled on the ends of two or several of the shafts 10. All theshafts 10 are mechanically interconnected through an axiallydisplaceable rod 13, which is coupled to the shaft 1t) throughdownwardspointing levers 14 attached to the shafts. The feeder pawls 9 willconsequently swing simultaneously between their raised position andtheir depressed position.

A feeder spring unit 15 is connected between the feeder carriage 5 andthe base plate 4. The feeder spring unit 15 .5. is shown in section inFIG. 6 and consists of a cylinder 16 and a piston 17 with a piston rod18 displaceable therein.

A coil spring 19 is arranged between the piston 17 and the one end wallof the cylinder 16. The cylinder 16 of the feeder spring unit 15 is, ascan be seen in FIG. 3, connected to the base plate 4, whereas the pistonrod 18, as can be seen in FIG. '6, is connected to a bracket arm 27projecting downwards from the lower side of the feeder carriage 5. InFIG. 3 this bracket arm 27 is hidden by other parts of the round feedingmechanism. The feeder spring unit 15 endeavours consequently to move thefeeder carriage 15 to the right in FIG. 3, that is in the dischargedirection. In FIG. 3, the feeder carriage is shown in the position,which it occupies at the end of a discharge movement.

The feeder carriage 5 is driven in synchronism with the firing of thegun by means of a cam slot bar 20, which is reciprocatingly movable inits longitudinal direction and is coupled to the recoiling mass of thegun so as to be moved to the right in FIG. 3 during the recuperationmovement of the gun and to the left during the recoil movement. In FIG.3 the cam slot bar 20 is shown in the position, which it occupies, whenthe recoiling mass of the gun is in its runout position. The feedercarriage 5 is coupled to the cam slot bar 20 through a link 21, which ispivoted about a pin '22 at its one end. The pin 22 is journalled in thebase plate 4. At its opposite end the link 21 is provided with a roller23 projecting into a groove 24 in the lower side of the feeder carriage5 at its discharge end. The lower side of the link 21 carries anadditional roller 25 running in a cam slot 26 in the cam slot bar 20.The structure and the operation of the drive mechanism is most readilyseen in FIG. 5, which shows schematically the cam slot bar 20 and thelink 21 seen from above and with the feeder carriage 5 removed. In FIG.5 the members are shown in full lines in the position occupied by them,when the recoiling mass of the gun is in the run-out position, and withdotted lines in the position occupied by them at the end of the recoilmovement. The cam slot 26 in the cam slot bar 20 has a narrow portionand a wide portion. The roller 25 on the link 21 lies in the widerportion of the slot 26, when the recoiling mass of the gun is in therun-out position. The roller 25 is then pressed against the S-shapedside of the cam slot 26 by the force from the feeder spring unit 15,which keeps the feeder carriage 5 in its discharge position. During therecoil movement of the gun the cam slot bar 20 is moved to the left inFIGS. 5 and 3 to the position shown with dotted lines in FIG. 5, wherebythe roller 25 will enter the narrow portion of the cam slot 26, so thatthe link 21 is pivoted about its pivot pin 22 and will, by means of theroller 23 projecting into the groove 24 in the feeder carriage 5, returnthe carriage 5 to the left in FIG. 3. During this movement the feederspring unit will be cocked. During the subsequent recuperation movementthe cam slot bar is returned to its right hand position in FIG. 5,whereby the spring feeder unit 15 will move the feeder carriage 5 in thedischarge direction to its discharge position.

When the recoiling mass of the gun is in the run-out position and thusthe cam slot bar 20 is in its right-hand position in FIGS. 3 and 5, thefeeder carriage 5 can, as can be seen in FIG. 5, due to the shape of thecam slot 26 be reciprocated without hindrance from the cam slot bar 20and its cam slot 26. This makes it possible to drive the feeder carriage5 manually, which is necessary, when the round magazine is to be emptiedand after the loading of the magazine, when the first round is to be fedto the ready position on the flaps 6. The manual drive mechanism for thefeeder carriage 5 is shown in detail in FIG. 6 and comprises adouble-armed lever 28 pivoted about a pin 29 on a nut 30. The nut 30 ismounted on a threaded shaft 31, which is mounted for rotation in thebase plate 4 and is coupled to a hand-operating crank 33 through levelgears 32. One end of the double-armed lever 28 is provided with a roller34 running in a guide groove 35 in the 6 stationary base plate 4. Theopposite end of the lever 28 is provided with a fork 36 having its legsdisposed on opposite sides of the piston rod 18 of the spring feederunit 15. The space between the legs of the fork 36 is such that thepiston rod 18 can be axially displaced within the fork 36. The legs ofthe fork 36 are provided with rollers 37, which can be brought toactagainst the bracket arm 27 projecting downwards from the feeder carriage5. In FIG. 6 the lever 28 and the nut 30 are shown in their inoperativeposition, which they occupy during firing, when the feeder carriage 5 isdriven from the recoiling mass of the gun. When the feeder carriage 5 isto be driven manually, the hand-operating crank 33 is rotated in thedirection indicated by an arrow 38, whereby the nut 30 is moved to theleft in FIG. 6 and the arm 28 is pivoted about its roller 34 in thedirection indicated by an arrow 39. The rollers 37 in the fork 36 willthen press against the bracket arm 27 on the feeder carriage 5 and movethe feeder carriage to the left in FIGS. 6 and 3, at the same time asthe feeder spring unit 15 is being cocked. When the feeder carriage 5 isfully returned to its neutral position, the hand-operating crank 33 isrotated in the opposite direction, whereby the feeder carriage 5 will bemoved by the feeder spring unit 15 in its discharge direction towardsits discharge position.

As can be seen in FIG. 3, the stationary base plate 4 is provided withtwo rows 40 and 40 of check pawls running parallel to the direction ofmovement of the feeder carriage 5 on opposite sides of the carriage sothat the row 40 of check pawls will cooperate with the forward ends ofthe rounds whereas the row 40 of check pawls cooperates with the rearends of the rounds. Both rows of check pawls are designed and controlledin exactly the same manner, with the exception that the check pawls havesomewhat different shapes in view of the different diameters of therounds at their forward ends and rear ends. It is consequentlysufficient to describe the design and the operation of the rear row 40of check pawls, which is best seen in FIG. 3. As can be seen in FIGS. 1,2 and 3, the row 40 of check pawls comprises two different types ofcheck pawls, viz. on the one hand five check pawls 41 pointing forwards,that is in the discharge direction of the feeder carriage 5, and on theother hand five check pawls 42 pointing rearwards, that is opposite tothe discharge direction of the feeder carriage 5. The forwards pointingcheck pawls 41 are arranged below each one of the round compartments 2in the round magazine 1 with exception for the round compartment closestto the discharge end of the feeder carriage 5, and are pivoted in avertical plane about stationary axes in the base plate 4 locatedstraight below the associated round compartments. The rearwards pointingcheck pawls 42 are in a corresponding way arranged below each one of theround compartments 2 with exception for the round compartment furtheraway from the discharge end of the feeder carriage 5 and are pivoted ina vertical plane about stationary axes in the base plate 4 locatedstraight below the associated round compartment. At those roundcompartments that are provided with a forwards pointing check pawl 41 aswell as a rearwards pointing check pawl 42, these check pawls arepivoted about the same axis. Beneath the pivot shafts on the check pawls41 and 42 there is a groove 43 in the base plate 4, in which groove tworods 44 and 45 are axially displaceable. The rod 44 is a control rod forthe forwards pointing check pawls 41 and is provided with a notch 46 foreach check pawl 41.

The check pawls 41 are provided with downwards pointing lugs 47projecting into the notches 46. The check pawls 41 are consequentlyinterconnected through the control rod 44, whereby they will assume thesame position and be pivoted simultaneously about their axes. The rod 45forms a corresponding control rod for the rearwards pointing check pawls42 and is provided with one notch 48 for each check pawl 42, the checkpawls being provided with downwards pointing lugs projecting into thenotches 48, whereby the check pawls 42 are interconnected through thecontrol rod 45 and will assume the same position and be pivotedsimultaneously about their axes. The bottom of the groove 43 is providedwith two elongated openings to the lower side of the base plate 4. Shorttaps 49 and d are attached to the lower side of the rod 44 and 45respectively and project downwards through said elongated openings, ascan be most readily seen in FIG. 4. At the lower side of the base plate4 the tap 49 attached to the rod 44 is provided with a head 51 and in acorresponding way the tap 50 attached to the rod 45 is provided with ahead 52. The heads 51 and 52 have a larger breadth than the elongatedopenings in the bottom of the groove 43, whereby the heads prevent therods 44 and 45 from being lifted out of the groove 43.

As can be seen in FIG. 4, a spring unit 53 is arranged between the twoheads 51 and 52 at the lower side of the base plate 4. The spring unit53 consists of a telescopic rod 54 and a coil spring 55 acting betweenthe two parts of the telescopic rod. The spring unit 53 endeavoursconsequently to move the rod 44 to the right and the rod 45 to the leftin FIGS. 3 and 4 and thus to pivot the check pawls 41 and '42 to theirraised positions shown in FIGS. 3 and 4. In this raised position theforwards pointing check pawls 41 are extending obliquely upwards in thedischarge direction of the round feeding carriage 5 between the roundslying in the space between the feeder carriage and the exit ends of theround compartments. The rearwards pointing check pawls 42, however, arein their raised positions extending obliquely upwards opposite to thedischarge direction of the feeder carriage between the rounds lying inthe space between the feeder carriage and the exit ends of the roundcompartments. From this raised position the forwards pointing checkpawls 41 as well as the rearwards pointing check pawls 42 can be pivotedto a depressed position, in which the check pawls lie underneath therounds in the space between the feeder carriage and the exit ends of theround compartments so that these rounds can pass above the check pawls.The forwards pointing check pawls 41 are brought into this depressedposition during the discharge movement of the feeder carriage 5 in thatthe rounds brought along by the feeder carriage depress the check pawls41 against the action of the spring unit 53, which will then be cocked.When each one of the forwards pointing check pawls 41 has been passed bya round brought along by the feeder carriage, the check pawls areautomatically returned to their raised position by the cocked springunit 53.

The rearwards pointing check pawls 42, on the contrary, are depressed bya special control mechanism comprising a rod 56 axially displaceable inthe base plate 4 and resting with its one end against the head 52attached to the control rod 45 for the rearwards pointing check pawls 42and having its opposite end coupled to a lever 57 attached to the oneend of a shaft 58 mounted for rotation in the base plate 4. The rod 56is kept in its neutral position shown in FIG. 4 by two coil springs 59.The neutral position of the rod 56 corresponds to the fully raisedposition of the rearwards pointing check pawls 42. The shaft 58 isprovided with an S-shaped lever 60 and the opposite end of the shaft(not visible in FIG. 4) is in the same way as shown in FIG. 4 coupled tothe rearwards pointing check pawls 42' in the fore row 40 of checkpawls. When the round feeder carriage 5 is moved from the position shownin FIGS. 3 and 4, which is the discharge position of the feedercarriage, to the left in FIGS. 3 and 4, the bracket arm 27 attached tothe lower side of the feeder carriage 5 and coupled to the piston rod 18of the feeder spring unit will be displaced to the left in FIG. 4 in thedirection of the arrow 61, whereby the lowermost end of the bracket arm27 will depress the S-shaped lever 60 on the shaft 58. In this way theshaft 58 is rotated and the rod 56 moved to the right in FIG. 4, asindicated by the arrow 62. The rod 56 will thereby push the control rod45 for the rearwards pointing check pawls 42 to the right in FIG. 4against the action of the spring unit 53, which will be cocked, so thatthe rearwards pointing check pawls 42 are brought into their depressedpositions. Through the cooperation between the bracket arm 27 on thefeeder carriage 5 and the S-shaped lever 60 on the shaft 58, therearwards pointing check pawls 42 are kept in this depressed positionduring the first part of the subsequent discharge movement of the feedercarriage, until each one of the rearwards pointing check pawls 42 hasbeen passed by a round lying in the space between the feeder carriageand the exit ends of the round compartments. During the later part ofthe discharge movement of the feeder carriage 5 the bracket arm 27 will,however, leave the S- shaped lever 60 on the shaft 58, whereby therearwards pointing check pawls 42 will be returned to their raisedposition by the cocked spring unit 53, before the discharge movement ofthe feeder carriage is completed. It should be noted that the manualdrive mechanism for the feeder carriage 5 shown in FIG. 6 has for thesake of clarity been omitted in FIG. 4. In the same way the controlmechanism for the rearwards pointing check pawls 42 shown in FIG. 4 hasbeen omitted in FIG. 6.

The round feeding mechanism described above for the round magazine 1 hasthe following cycle of operation. Let it be assumed that the gun hasbeen firing for some time so that some rounds have been fired. The roundcompartment 2 in the round magazine 1 furthest away from the gun istherefore partially emptied, whereas the remaining five roundcompartments are completely filled with rounds. Let it further beassumed that the recoiling mass of the gun is presently in its run-outposition. This means that the round feeder carriage 5 is in itsdischarge position shown in FIG. 3 and has just delivered a round to theready position on the flaps 6 underneath the completely raiseddown-feeder 8. The loading tray 7 is empty, as a round has just beenrammed into the loading chamber in the breech ring of the gun by theramming mechanism of the gun. All round feeder pawls on the round feedercarriage 5 are in the raised position and the pair of the feeder pawlsclosest to the discharge end of the feeder carriage are lying outsidethe actual round magazine, as they have just delivered a round onto theflaps 6. The remaining five pairs of feeder pawls on the feeder carriage5 lie behind one each of the rounds, which lie in the space between thefeeder carriage and the lower exit ends of the round compartments 5straight below the five round compartments closest to the discharge endof the feeder carriage. There is also a round in the space between thefeeder carriage and the exit end of the round compartment furthest awayfrom the discharge end of the feeder carriage, but in this position nofeeder pawls on the feeder carriage 5 lie behind this round. The roundsin the space between the feeder carriage 5 and the exit ends of theround compartments 2 do not rest directly upon the feeder carriage, butthe rear ends of these rounds are resting on a rib 63 on the base plate4, as can be seen in FIG. 3, whereas the fore ends of the rounds areresting upon a corresponding rib (not visible in FIG. 3) on the baseplate 4 on the outside of the row 40' of check pawls. In the rib 63 anumber of spring-loaded guide levers 64 corresponding to the number ofround compartments 2 are pivoted in a vertical plane so as to bedepressed by the rounds lying in the space between the feeder carriage 5and the exit ends of the round compartments. In their depressed positionthese guide levers form a guide rib in front of the flange at the bottomof the shells of the rounds and prevent thereby the rounds from beingdisplaced in their longitudinal direction. Each one of the roundcompartments 2 is at its lower exit end provided with a locking flap 65,as can be seen in FIGS. 1 and 2. The locking flap 65 can be pivoted intothe round compartments so as to prevent the rounds from leaving thecompartments or be pivoted into the walls of the round compartments sothat rounds can be discharged from the compartments by the spring forcepermanently acting upon the stacks of rounds in the round compartments.Each one of these locking flaps 65 is in any suitable manner not shownin the drawing controlled by a feeler member, which registers whetherthere is any round lying in the space between the feeder carriage andthe exit end of the associated round compartment. If there is a round inthis space, the locking flap 65 is kept in its locking position so thatit will be in the way of the lowermost round in the round compartmentand prevent this round from being discharged from the round compartmentand from resting on the round lying underneath the round compartmentbetween the exit end of the round compartment and the feeder carriage.If, however, there is no round in the space between the feeder carriageand the exit end of the round compartment, the locking flap 65 is movedto the side so that the lowermost round in the round compartment will bepushed downwards into the space between the feeder carriage and the exitend of the round compartment, whereafter the locking flap 65 isimmediatley returned to its locking position in that the feeler membercontrolling the locking flap 65 is actuated by the round just dischargedfrom the round compartment. In the position assumed above all lockingflaps 65 are consequently projecting into their associated roundcompartments. Further the forwards pointing check pawls 41 as well asthe rearwards pointing check pawls 42 are in their raised positions.

When subsequently a round is fired and the recoiling mass of the gunrecoils, the round feeding carriage is moved in the manner previouslydescribed to the left in FIGS. 1, 2 and 3. The spring-loaded roundfeeder pawls 9 on the feeder carriage 5 are then depressed to theirdepressed position by the rounds lying above the feeder carriage, asthese rounds are prevented from being brought along in the movement ofthe feeder carriage by the raised forwards pointing check pawls 41, asshown in FIG. 2. Obviously, no such forwards pointing check pawls isnecessary for the round lying furthest away from the discharge end ofthe feeder carriage, as this round is prevented from being brought alongin the movements of the feeder carriage by the outer wall of the roundmagazine. During the last portion of the movement of the feeder carriage5 to the left in FIGS. 1, 2 and 3 the rearwards pointing check pawls 42are pivoted to their depressed positions, in the manner previouslydescribed, by the control mechanism shown in FIG. 4 and are kept in thisdepressed position during the remaining part of the return movement ofthe feeder carriage 5. During the recoil movement of the recoiling massthe downfeeder 8 will, as already mentioned, push the round resting onthe flaps 6 downwards between the flaps onto the loading tray 7. At theend of the recoil movement the ready position on the flaps 6 isconsequently empty, whereas a round is resting upon the loading tray 7.Furthermore, the round feeder carriage 5 is fully returned to itsleft-hand position in FIGS. 1, 2 and 3, wherefore the round feeder pawls9 have under spring action returned to their raised position and liebehind one each of the rounds lying between the feeder carriage 5 andthe exit ends of the round compartments. Also the forwards pointingcheck pawls 4 are in their raised position,' whereas the rearwardspointing check pawls 42 are in their depressed position, as explainedabove.

During the subsequent recuperation movement of the recoiling mass thefeeder carriage 5 is, as previously described, moved to the right inFIGS. 1, 2 and 3 and the round feeder pawls 9 on the feeder carriagewill bring along the rounds lying in the space between the feedercarriage and the eXit ends of the round compartments in this movement.The forwards pointing check pawls 41 will then be depressed to theirdepressed positions by these rounds, which can consequently pass abovethe forwards ointing check pawls. The rearwards pointing check pawls 42are, as previously described, kept in their depressed p0 sition by theircontrol mechanism, until each one of these pawls has been passed by oneround. Thereafter the rearwards pointing check pawls 42 are released andwill under spring action gradually return to their raised position, whenthe discharge movement of the feeder carriage 5 and of the roundsbrought along by the feeder carriage continues, as shown in FIG. 1,wherein the rearwards pointing check pawls 42 have just started toreturn to their raised positions behind the rounds, which have justpassed the check pawls. The round closest to the discharge end of thefeeder carriage 5 is pushed by the first pair of round feeder pawls downonto the flaps 6 in that the round is pushed by these feeder pawls pasta spring-loaded check plunger 68. When the discharge movement of thefeeder carriage 5 is completed, the rearwards pointing check pawls 42are completely raised and in a position to retard and stop the roundslying in the space between the feeder carriage and the exit ends of theround compartments. A considerable velocity has been imparted to theserounds during the discharge movement of the feeder carriage. The impactfrom the rounds upon the rearwards pointing check pawls 42 is absorbedby a spring damper 66 mounted on the base plate. This spring damper willretard the movement of the control rod 45 for the rearwards pointingcheck pawls 42. The movement of the round, which is moved by the feedercarriage 5 to the position straight below the round compartment closestto the discharge end of the feeder carriage will be retarded and stoppedby the spring-loaded check plunger 68. The row 40 of check pawls couldof course include a rearwards pointing check pawl also for theretardation of this round, in which case it would be necessary, however,to lengthen the base plate 4 to the right in FIGS. 1, 2 and 3. In orderto save space it is therefore preferable to provide the springloadedcheck plunger 68 for the retardation of this round.

When during the discharge movement of the feeder carriage the round atthe rear end of the feeder carriage leaves the space between the feedercarriage and the exit end of the round compartment furthest away fromthe discharge end of the feeder carriage, the locking flap 65 of thisround compartment will, as shown in FIG. 1, be swung out of the way,whereby the lowermost round in this round compartment will be dischargedfrom the round compartment downwards into the space between the lowerend of the round compartment and the base plate behind the rearmost pairof round feeder pawls on the feeder carriage, whereafter the lockingflap 65 is immediately returned to its locking position. During therecuperation movement of the recoiling mass and thus during thedischarge movement of the feeder carriage 5 the down-feeder 8 is, aspreviously described returned to its upper position and willconsequently not prevent the feeder carriage 5 from delivering a newround to the flaps 6 at the end of its discharge movement.

As it should be possible to provide a gun with two round magazines ofthe type described each having its round-feeding mechanism, it must bepossible to interrupt the discharging of rounds from the one roundmagazine, when the rounds are to be taken from the other magazine. Withthis object the round-feeding mechanism according to the invention shownin the drawing and described above is provided with a cam path 67 (seeFIG. 3) attached to the upper end of a vertical rod 69, which can bemanually rotated by means of a control rod 70 so that the cam path 67 ismoved from an inoperative position shown in full lines in FIG. 3 to anoperative position shown in dotted lines. In the latter position the campath 67 will affect a lever 71 attached to one of the shafts 10 for theround feeder pawls 9 in such a way that all the round feeder. pawls 9,which are interconnected through the rod 13 and the shafts 10 aspreviously described, are lowered to their depressed position and arekept in this position during the entire reciprocating movement of thefeeder carriage 5, except immediately close to the discharge position ofthe feeder carriage shown in FIG. 3. If the cam path 67 is moved bymeans of the manually operated control rod 70 to its operative positionshown in dotted lines, the feeder carriage 5 will consequently notdischarge any rounds from the round magazine in spite of the fact thatthe feeder carriage is reciprocated in step with the firing of the gun.

I claim:

1. A round feeding mechanism for an automatic gun having a roundmagazine including several vertical round compartments located side byside, each holding a stack of rounds lying one upon the other and havinga lower open exit end for said rounds, for discharging the rounds heldin said magazine one by one in a predetermined order, comprising ahorizontal round feeder carriage underneath said round magazine andspaced from said lower exit ends of said round compartments by adistance at least corresponding to the diameter of said rounds, saidround feeder carriage being reciprocatingly movable perpendicularly tothe longitudinal direction of the rounds in said round compartments overa distance corresponding to the spacing between the center lines inadjacent round compartments between a neutral position and a dischargeposition for discharging at the end of a discharge movement from saidneutral position to said discharge position a round at its forwarddischarge end and being provided with a number of round feeder pawlscorresponding to the. number of round compartments disposed in thedirection of movement of the carriage with a mutual spacingcorresponding to the center line spacing between adjacent roundcompartments, two rows of check pawls disposed parallel to the directionof movement of said carriage on opposite side of the carriage, each oneof said rows comprising a first check pawl for each one of said roundcompartments except for the round compartment furthest away from saiddischarge end of said carriage, said first check pawls being pivoted ina vertical plane parallel to the direction of movement of said carriageabout stationary axes located straight below associated ones of saidround compartments so as to be swingable between a raised position, inwhich said first check pawls are extending obliquely upwards opposite tothe direction of said discharge movement of said carriage between roundsdisposed in the space between said carriage and said lower exit ends ofsaid round compartments, and a depressed position, in which said firstcheck pawls lie beneath said rounds and can be passed by them, andcontrol means for said first check pawls responsive to the movement ofsaid round feeder carriage for moving said first check pawls to saiddepressed position before the beginning of said discharge movement ofsaid round feeder carriage and for maintaining them in said depressedposition during the first part of said discharge movement of saidcarriage, until each one of said first check pawls has been passed by around disposed in said space between said carriage and said lower exitends of said round compartments, and for returning said first checkpawls to said raised position before the end of said discharge movementof said carriage.

2. A mechanism as claimed in claim 1, wherein each one of said two rowsof check pawls comprises a second check pawl for each one of said roundcompartments except for the round compartment closest to said dischargeend of said round feeder carriage, said second check pawls being pivotedin a vertical plane parallel to the direction of movement of saidcarriage about stationary axes located straight below associated ones ofsaid round compartments so as to be swingable between a raised position,in which said second check pawls are extending upwards in the directionof said discharge movement of said carriage between the rounds disposedin the space between said carriage and said lower exit ends of saidround compartments, and a depressed position, in which said second checkpawls lie beneath said rounds and can be passed by them, and comprisingspring means urging said second check pawls towards said raisedposition.

3. A mechanism as claimed in claim 2, comprising for each one of saidtwo rows of check pawls a first axially displaceable rod parallel to theassociated row of check pawls, said first rod being coupled to saidfirst check pawls of said associated row so as to swing said first checkpawls about their pivot axes upon axial displacement of said first rod,and a corresponding second axially displacement rod parallel to saidassociated row of check pawls, said second rod being coupled to saidsecond check pawls of said associated row so as to swing said secondcheck pawls about their pivot axes upon axial displacement of saidsecond rod, spring means urging said first and second rods in directionscorresponding to rotations of 7 said first and second check pawlsrespectively towards their raised positions, said first rod beingcoupled to control means responsive to the movement of said round feedercarriage so as to be displaced during the return movement of saidcarriage from its discharge position to its neutral position against theaction of said spring means to a position bringing said first checkpawls into their depressed position and to be maintained in saidposition during the first part of the subsequent discharge movement ofsaid round feeder carriage.

4. A mechanism as claimed in claim 3, wherein said spring means comprisea spring acting between said first and second rods.

5. A mechanism as claimed in claim 1, wherein said round feeder pawls onsaid round feeder carriage are pivoted in a vertical plane parallel tothe direction of movement of said carriage so as to be swingable betweena raised position, in which they extend obliquely upwards in thedirection of said discharge movement of said carriage between the roundsdisposed in the space -between said carriage and said lower exit ends ofsaid round compartments, and a depressed position, in which they liebeneath said rounds and can pass underneath them, and comprising springmeans urging said round feeder pawls towards their raised position.

6. A mechanism as claimed'in claim 5, wherein said round feeder pawlsare mechanically interconnected so as to swing simultaneously betweentheir raised and depressed positions, and comprising can path meansdisplaceable between an operative and an inoperative position forkeeping, when in said operative position, said round feeder pawls intheir depressed position during substantially the entire dischargemovement of said round feeder carriage, whereby no rounds will bebrought along in the discharge movement of said carriage.

7. A mechanism as claimed in claim 1, wherein said rounder feedercarriage is coupled to the recoiling mass of the gun so as to be movedtowards said discharge position during the recuperation movement oif therecoiling mass and towards said neutral position during the recoilmovement of the recoiling mass.

8. A mechanism as claimed in claim 1, comprising manually operated meansfor reciprocating said round feeder carriage between said dischargeposition and said neutral position.

References Cited UNITED STATES PATENTS 2,790,356 4/1957 Gerdin 89332,988,963 6/1961 Goodhoe 89-33 3,306,165 2/1967 Christiansson 8933BENJAMIN A. BORCHELT, Primary Examiner.

S. C. BENTLEY, Assistant Examiner.

1. A ROUND FEEDING MECHANISM FOR AN AUTOMATIC GUN HAVING A ROUNDMAGAZINE INCLUDING SEVERAL VERTICAL ROUND COMPARTMENTS LOCATED SIDE BYSIDE, EACH HOLDING A STACK OF ROUNDS LYING ONE UPON THE OTHER AND HAVINGA LOWER OPEN EXIT END FOR SAID ROUNDS, FOR DISCHARGING THE ROUNDS HELDIN SAID MAGAZINE ONE BY ONE IN A PREDETERMINED ORDER, COMPRISING AHORIZONTAL ROUND FEEDER CARRIAGE UNDERNEATH SAID ROUND MAGAZINE ANDSPACED FROM SAID LOWER EXIT ENDS OF SAID ROUND COMPARTMENTS BY ADISTANCE AT LEAST CORRESPONDING TO THE DIAMETER OF SAID ROUNDS, SAIDROUND FEEDER CARRIAGE BEING RECIPROCATINGLY MOVABLE PERPENDICULARLY TOTHE LONGITUDINAL DIRECTION OF THE ROUNDS IN SAID ROUND COMPARTMENTS OVERA DISTANCE CORRESPONDING TO THE SPACING BETWEEN THE CENTER LINES INADJACENT ROUND COMPARTMENTS BETWEEN A NEUTRAL POSITION AND A DISCHARGEPOSITION FOR DISCHARGING AT THE END OF A DISCHARGE MOVEMENT FROM SAIDNEUTRAL POSITION TO SAID DISCHARGE POSITION A ROUND AT ITS FORWARDDISCHARGE END AND BEING PROVIDED WITH A NUMBER OF ROUND FEEDER PAWLSCORRESPONDING TO THE NUMBER OF ROUND COMPARTMENTS DISPOSED IN THEDIRECTION OF MOVEMENT OF THE CARRIAGE WITH A MUTUAL SPACINGCORRESPONDING TO THE CENTER LINE SPACING BETWEEN ADJACENT ROUNDCOMPARTMENTS, TWO ROWS OF CHECK PAWLS DISPOSED PARALLEL TO THE DIRECTIONOF MOVEMENT OF SAID CARRIAGE ON OPPOSITE SIDE OF THE CARRIAGE, EACH ONEOF SAID ROWS COMPRISING A FIRST CHECK PAWL FOR EACH ONE OF SAID ROUNDCOMPARTMENTS EXCEPT FOR THE ROUND COMPARTMENT FURTHEST AWAY FROM SAIDDISCHARGE END OF SAID CARRIAGE, SAID FIRST CHECK PAWLS BEING PIVOTED